The Sustainable Pharma Futures service combines Cello's experience of the pharma industry with Forster's expertise as a social-change PR firm, according to the agencies.
The partnership, announced last week, consists of a single, dedicated team drawn from the two agencies.
It aims to use comms to help shape and bring to life sustainability policies within companies and then engage stakeholders to build reputation.
Sustainability is often focused solely on charitable giving and not connected to other work happening across organisations, such as employee wellbeing, product-packaging innovations and facilities management, the agencies claim.
The new service will bring these elements together to help identify opportunities to grow or develop existing strengths, and amplify the activity through targeted communications.
Amanda Powell-Smith, chief executive of Forster Communications, said: "The pharmaceutical industry is based on changing society for the better. Not only does it create life-saving treatments, but it also spends billions of pounds on educating and supporting communities around health issues across the world.
"But too often, the work done is siloed internally and hidden from view. It is not joined-up or realising its full value in driving positive change for the business, its stakeholders and society."
She added: "We believe that the majority of pharmaceutical businesses are sitting on untapped potential and want to make sustainability good for society and good for business."
Jo Taylor, corporate affairs head at Cello, commented: "The combined skills and experience of our two organisations give corporate affairs directors instant access to knowledge and insights on how they can build their role as ethical, responsible organisations that are making a difference."
She said: "This is no longer a 'nice-to-do', it’s about securing a future for pharmaceutical businesses to operate in."
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